BS EN 13373:2020 pdf free.Natural stone test methods ——Determination of geometric characteristics on units.
BS EN 13373 This document describes methods for verifying the geometric characteristics of products of natural stone such as rough blocks, rough slabs, finished products for cladding, flooring, stairs and modular tiles and paving units (slabs, setts and kerbs). These methods can be applied in the case of a dispute between two parties, they are not compulsory for production control.Other measuring equipment can be used as long as their precision can be demonstrated to be equal or better than the ones mentioned here.It is essential that all weighing, measuring and testing equipment are calibrated or retraceable to measurement standards and regularly inspected according to documented procedures, frequencies and criteria. It is important that the expression of the dimensional characteristics is in accordance with the appropriate class of the measured product.一The net length Xnet and the net height Znet of the slab are measured in the following manner:一Define the largest rectangle that can still be inscribed within the rough slab.-Estimate and trace the net dimensions of the slab Xnet and Znet (see Figure 4).
-Take measurements expressed in metres to the nearest 0,01 m at i places (minimum 3) for each direction Xxi and Zi where visually the smallest dimensions occur.If the tolerance class of the dimension being measured is not known then the maximum measuring error of the measuring device shall be not more than 0,1 mm.The device used for measuring the thickness of webs and shells shall have a jaw of at least 10 mm in length. The average rough measurement of the thickness of the element is taken according to the method described in 6.4.1. -The nominal thickness is calculated by subtracting the maximum depth of hollows, obtained with the profile gauge according to 6.4.3, from the average rough thickness. 一For sawn surfaces, the nominal thickness is taken to be equal to the rough thickness.Measurement of the deviation from flatness for elements with sawn edges and having a sawn, honed or polished surface finish.BS EN 13373 pdf download.